JRTextExporter (JasperReports 6.1.1 API)

java.lang.Object
- net.sf.jasperreports.engine.JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
- - net.sf.jasperreports.engine.export.JRTextExporter

All Implemented Interfaces:

JRExporter<ExporterInput,TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput>, Exporter<ExporterInput,TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput>
```
public class JRTextExporter
extends JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
```
Exports filled reports in plain text format. The text exporter allows users to define a custom character resolution (the number of columns and rows in text format). Since the character resolution is mapped on the actual pixel resolution, every character corresponds to a rectangle of pixels. If a certain text element has a smaller size in pixels (width, height, or both) than the number of pixels that map to a character, the text element will not be rendered.
The text exporter will yield the better results if the space needed for displaying a text is large. So users have to either design reports with few text or export to big text pages. Another good practice is to arrange text elements at design time as similar as possible to a grid.
The text exporter tries to convert the JasperReports document into a simple text document with a fixed page width and height, measured in characters. Users can specify the desired page width and height, and the engine will make the best effort to fit text elements into the corresponding text page. The basic idea of the algorithm is to convert pixels to characters (to find a pixel/character ratio). To achieve this, use the following configuration settings (see TextReportConfiguration):
- getCharWidth() and getCharHeight() - these specify how many pixels in the original report should be mapped onto a character in the exported text.
- getPageWidthInChars() and getPageHeightInChars() - these specify the text page width and height in characters.
Note that both width and height must be specified and that character sizes have priority over page sizes.
Since the algorithm causes loss of precision, a few precautions should be taken when creating templates that will eventually be exported to plain text:
- Report sizes and text page sizes should be divisible (for example, specify a template width of 1,000 pixels and a page width of 100 characters, resulting in a character width of 10 pixels).
- Text element sizes should also follow the preceding rule (for example, if the character height is 10 pixels and a particular text element is expected to span two rows, then the text element should be 20 pixels tall).
- For best results, text elements should be aligned in a grid-like fashion.
- Text fields should not be too small. Following are two examples of problems that this can cause:
  - If the element height is smaller than the character height, then the element will not appear in the exported text file.
  - If the character width is 10 and the element width is 80, then only the first eight characters will be displayed.
Users can specify the text that should be inserted between two subsequent pages by using the getPageSeparator() exporter configuration setting. The default value is two blank lines.
The line separator to be used in the generated text file can be specified using the getLineSeparator() exporter configuration setting. This is most useful when you want to force a particular line separator, knowing that the default line separator is operating system dependent, as specified by the line.separator system property of the JVM.
Check the supplied /demo/samples/text sample to see the kind of output this exporter can produce.
Author:

Ionut Nedelcu (ionutned@users.sourceforge.net)

See Also:
TextExporterConfiguration, TextReportConfiguration

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

protected class JRTextExporter.ExporterContext
- Nested classes/interfaces inherited from class net.sf.jasperreports.engine.JRAbstractExporter
  JRAbstractExporter.BaseExporterContext, JRAbstractExporter.PageRange

Nested Classes
Modifier and Type	Class and Description
`protected class`	`JRTextExporter.ExporterContext`

Field Summary

Fields
Modifier and Type	Field and Description
`protected float`	`charHeight`
`protected float`	`charWidth`
`static java.lang.String`	`EXCEPTION_MESSAGE_KEY_CHARACTER_HEIGHT_NEGATIVE`
`static java.lang.String`	`EXCEPTION_MESSAGE_KEY_CHARACTER_WIDTH_NEGATIVE`
`static java.lang.String`	`EXCEPTION_MESSAGE_KEY_REQUIRED_POSITIVE_PAGE_OR_CHARACTER_HEIGHT`
`static java.lang.String`	`EXCEPTION_MESSAGE_KEY_REQUIRED_POSITIVE_PAGE_OR_CHARACTER_WIDTH`
`protected boolean`	`isTrimLineRight`
`protected java.lang.String`	`lineSeparator`
`protected int`	`pageHeightInChars`
`protected java.lang.String`	`pageSeparator`
`protected int`	`pageWidthInChars`
`protected static java.lang.String`	`systemLineSeparator`
`protected java.io.Writer`	`writer`

Constructor Summary

Constructors
Constructor and Description

JRTextExporter()

JRTextExporter(JasperReportsContext jasperReportsContext)

Constructors
Constructor and Description
`JRTextExporter()`
`JRTextExporter(JasperReportsContext jasperReportsContext)`

Method Summary

Methods
Modifier and Type	Method and Description
`protected void`	`ensureOutput()`
`protected void`	`exportElements(java.util.List<JRPrintElement> elements)`
`protected void`	`exportPage(JRPrintPage page)` Exports a page to the output writer.
`void`	`exportReport()` Performs the export.
`protected void`	`exportReportToWriter()`
`protected void`	`exportText(JRPrintText element)` Renders a text and places it in the output matrix.
`protected java.lang.Class<TextExporterConfiguration>`	`getConfigurationInterface()`
`java.lang.String`	`getExporterKey()`
`java.lang.String`	`getExporterPropertiesPrefix()` Returns the properties prefix for the current exporter.
`protected int`	`getHeightInChars(int height)` Transforms height from pixel space to character space.
`protected java.lang.Class<TextReportConfiguration>`	`getItemConfigurationInterface()`
`protected JRStyledText`	`getStyledText(JRPrintText textElement)`
`protected int`	`getWidthInChars(int width)` Transforms width from pixel space to character space.
`protected void`	`initExport()`
`protected void`	`initReport()`

Methods inherited from class net.sf.jasperreports.engine.JRAbstractExporter
createFilter, defaultParseNumber, ensureInput, ensureJasperReportsContext, getBooleanCellValue, getCurrentConfiguration, getCurrentItemConfiguration, getCurrentJasperPrint, getCustomHandler, getDateCellValue, getDateFormat, getExporterContext, getExporterInput, getExporterOutput, getHyperlinkProducer, getJasperReportsContext, getLocale, getNumberCellValue, getNumberFormat, getOffsetX, getOffsetY, getPageRange, getParameter, getParameters, getPropertiesUtil, getReportContext, getStyledText, getTextFormatFactoryClass, getTextLocale, getTextTimeZone, getTextValue, getTextValueString, insideFrame, reset, resetClassLoader, resetExportContext, restoreElementOffsets, setClassLoader, setConfiguration, setConfiguration, setCurrentExporterInputItem, setExporterInput, setExporterOutput, setFrameElementsOffset, setJasperPrint, setJasperReportsContext, setOffset, setOffset, setParameter, setParameters, setReportContext

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - EXCEPTION_MESSAGE_KEY_REQUIRED_POSITIVE_PAGE_OR_CHARACTER_WIDTH
```
public static final java.lang.String EXCEPTION_MESSAGE_KEY_REQUIRED_POSITIVE_PAGE_OR_CHARACTER_WIDTH
```
    See Also:
    Constant Field Values
  - EXCEPTION_MESSAGE_KEY_CHARACTER_WIDTH_NEGATIVE
```
public static final java.lang.String EXCEPTION_MESSAGE_KEY_CHARACTER_WIDTH_NEGATIVE
```
    See Also:
    Constant Field Values
  - EXCEPTION_MESSAGE_KEY_REQUIRED_POSITIVE_PAGE_OR_CHARACTER_HEIGHT
```
public static final java.lang.String EXCEPTION_MESSAGE_KEY_REQUIRED_POSITIVE_PAGE_OR_CHARACTER_HEIGHT
```
    See Also:
    Constant Field Values
  - EXCEPTION_MESSAGE_KEY_CHARACTER_HEIGHT_NEGATIVE
```
public static final java.lang.String EXCEPTION_MESSAGE_KEY_CHARACTER_HEIGHT_NEGATIVE
```
    See Also:
    Constant Field Values
  - writer
```
protected java.io.Writer writer
```
  - pageWidthInChars
```
protected int pageWidthInChars
```
  - pageHeightInChars
```
protected int pageHeightInChars
```
  - charWidth
```
protected float charWidth
```
  - charHeight
```
protected float charHeight
```
  - pageSeparator
```
protected java.lang.String pageSeparator
```
  - lineSeparator
```
protected java.lang.String lineSeparator
```
  - isTrimLineRight
```
protected boolean isTrimLineRight
```
  - systemLineSeparator
```
protected static final java.lang.String systemLineSeparator
```
- Constructor Detail
  - JRTextExporter
```
public JRTextExporter()
```
    See Also:
    JRTextExporter(JasperReportsContext)
  - JRTextExporter
```
public JRTextExporter(JasperReportsContext jasperReportsContext)
```
- Method Detail
  - getConfigurationInterface
```
protected java.lang.Class<TextExporterConfiguration> getConfigurationInterface()
```
    Specified by:
    
    getConfigurationInterface in class JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
  - getItemConfigurationInterface
```
protected java.lang.Class<TextReportConfiguration> getItemConfigurationInterface()
```
    Specified by:
    
    getItemConfigurationInterface in class JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
  - ensureOutput
```
protected void ensureOutput()
```
    Specified by:
    
    ensureOutput in class JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
  - exportReport
```
public void exportReport()
                  throws JRException
```
    Description copied from interface: Exporter
    
    Performs the export.
    
    Specified by:
    
    exportReport in interface Exporter<ExporterInput,TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput>
    
    Specified by:
    
    exportReport in class JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
    
    Throws:
    
    JRException
  - initExport
```
protected void initExport()
```
    Overrides:
    
    initExport in class JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
  - initReport
```
protected void initReport()
```
    Overrides:
    
    initReport in class JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
  - exportReportToWriter
```
protected void exportReportToWriter()
                             throws JRException,
                                    java.io.IOException
```
    Throws:
    
    JRException
    
    java.io.IOException
  - exportPage
```
protected void exportPage(JRPrintPage page)
                   throws java.io.IOException
```
    Exports a page to the output writer. Only text elements within the page are considered. For each page, the engine creates a matrix of characters and each rendered text element is placed at the appropriate position in the matrix. After all texts are parsed, the character matrix is sent to the output writer.
    
    Throws:
    
    java.io.IOException
  - exportElements
```
protected void exportElements(java.util.List<JRPrintElement> elements)
```
  - exportText
```
protected void exportText(JRPrintText element)
```
    Renders a text and places it in the output matrix.
  - getHeightInChars
```
protected int getHeightInChars(int height)
```
    Transforms height from pixel space to character space.
  - getWidthInChars
```
protected int getWidthInChars(int width)
```
    Transforms width from pixel space to character space.
  - getStyledText
```
protected JRStyledText getStyledText(JRPrintText textElement)
```
    Overrides:
    
    getStyledText in class JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
  - getExporterKey
```
public java.lang.String getExporterKey()
```
    Specified by:
    
    getExporterKey in class JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
  - getExporterPropertiesPrefix
```
public java.lang.String getExporterPropertiesPrefix()
```
    Description copied from class: JRAbstractExporter
    
    Returns the properties prefix for the current exporter.
    
    Specified by:
    
    getExporterPropertiesPrefix in class JRAbstractExporter<TextReportConfiguration,TextExporterConfiguration,WriterExporterOutput,JRTextExporterContext>
    
    Returns:
    the properties prefix for the current exporter

Class JRTextExporter

Nested Class Summary

Nested classes/interfaces inherited from class net.sf.jasperreports.engine.JRAbstractExporter

Field Summary

Fields inherited from class net.sf.jasperreports.engine.JRAbstractExporter

Constructor Summary

Method Summary

Methods inherited from class net.sf.jasperreports.engine.JRAbstractExporter

Methods inherited from class java.lang.Object

Field Detail

EXCEPTION_MESSAGE_KEY_REQUIRED_POSITIVE_PAGE_OR_CHARACTER_WIDTH

EXCEPTION_MESSAGE_KEY_CHARACTER_WIDTH_NEGATIVE

EXCEPTION_MESSAGE_KEY_REQUIRED_POSITIVE_PAGE_OR_CHARACTER_HEIGHT

EXCEPTION_MESSAGE_KEY_CHARACTER_HEIGHT_NEGATIVE

writer

pageWidthInChars

pageHeightInChars

charWidth

charHeight

pageSeparator

lineSeparator

isTrimLineRight

systemLineSeparator

Constructor Detail

JRTextExporter

JRTextExporter

Method Detail

getConfigurationInterface

getItemConfigurationInterface

ensureOutput

exportReport

initExport

initReport

exportReportToWriter

exportPage

exportElements

exportText

getHeightInChars

getWidthInChars

getStyledText

getExporterKey

getExporterPropertiesPrefix